limine/common/lib/misc.c
2022-10-07 07:49:47 +02:00

275 lines
7.7 KiB
C

#include <stdint.h>
#include <stddef.h>
#include <stdarg.h>
#include <lib/libc.h>
#include <lib/misc.h>
#include <lib/print.h>
#include <lib/trace.h>
#include <lib/real.h>
#include <fs/file.h>
#include <mm/pmm.h>
#if defined (UEFI)
EFI_SYSTEM_TABLE *gST;
EFI_BOOT_SERVICES *gBS;
EFI_RUNTIME_SERVICES *gRT;
EFI_HANDLE efi_image_handle;
EFI_MEMORY_DESCRIPTOR *efi_mmap = NULL;
UINTN efi_mmap_size = 0, efi_desc_size = 0;
UINT32 efi_desc_ver = 0;
#endif
bool editor_enabled = true;
bool parse_resolution(size_t *width, size_t *height, size_t *bpp, const char *buf) {
size_t res[3] = {0};
const char *first = buf;
for (size_t i = 0; i < 3; i++) {
const char *last;
size_t x = strtoui(first, &last, 10);
if (first == last)
break;
res[i] = x;
if (*last == 0)
break;
first = last + 1;
}
if (res[0] == 0 || res[1] == 0)
return false;
if (res[2] == 0)
res[2] = 32;
*width = res[0], *height = res[1];
if (bpp != NULL)
*bpp = res[2];
return true;
}
// This integer sqrt implementation has been adapted from:
// https://stackoverflow.com/questions/1100090/looking-for-an-efficient-integer-square-root-algorithm-for-arm-thumb2
uint64_t sqrt(uint64_t a_nInput) {
uint64_t op = a_nInput;
uint64_t res = 0;
uint64_t one = (uint64_t)1 << 62;
// "one" starts at the highest power of four <= than the argument.
while (one > op) {
one >>= 2;
}
while (one != 0) {
if (op >= res + one) {
op = op - (res + one);
res = res + 2 * one;
}
res >>= 1;
one >>= 2;
}
return res;
}
size_t get_trailing_zeros(uint64_t val) {
for (size_t i = 0; i < 64; i++) {
if ((val & 1) != 0) {
return i;
}
val >>= 1;
}
return 64;
}
uint32_t oct2bin(uint8_t *str, uint32_t max) {
uint32_t value = 0;
while (max-- > 0) {
value <<= 3;
value += *str++ - '0';
}
return value;
}
uint32_t hex2bin(uint8_t *str, uint32_t size) {
uint32_t value = 0;
while (size-- > 0) {
value <<= 4;
if (*str >= '0' && *str <= '9')
value += (uint32_t)((*str) - '0');
else if (*str >= 'A' && *str <= 'F')
value += (uint32_t)((*str) - 'A' + 10);
else if (*str >= 'a' && *str <= 'f')
value += (uint32_t)((*str) - 'a' + 10);
str++;
}
return value;
}
#if defined (UEFI)
no_unwind bool efi_boot_services_exited = false;
bool efi_exit_boot_services(void) {
EFI_STATUS status;
EFI_MEMORY_DESCRIPTOR tmp_mmap[1];
efi_mmap_size = sizeof(tmp_mmap);
UINTN mmap_key = 0;
gBS->GetMemoryMap(&efi_mmap_size, tmp_mmap, &mmap_key, &efi_desc_size, &efi_desc_ver);
efi_mmap_size += 4096;
status = gBS->FreePool(efi_mmap);
if (status) {
goto fail;
}
status = gBS->AllocatePool(EfiLoaderData, efi_mmap_size, (void **)&efi_mmap);
if (status) {
goto fail;
}
EFI_MEMORY_DESCRIPTOR *efi_copy;
status = gBS->AllocatePool(EfiLoaderData, efi_mmap_size * 2, (void **)&efi_copy);
if (status) {
goto fail;
}
const size_t EFI_COPY_MAX_ENTRIES = (efi_mmap_size * 2) / efi_desc_size;
size_t retries = 0;
retry:
status = gBS->GetMemoryMap(&efi_mmap_size, efi_mmap, &mmap_key, &efi_desc_size, &efi_desc_ver);
if (retries == 0 && status) {
goto fail;
}
// Be gone, UEFI!
status = gBS->ExitBootServices(efi_image_handle, mmap_key);
if (status) {
if (retries == 128) {
goto fail;
}
retries++;
goto retry;
}
#if defined(__x86_64__) || defined(__i386__)
asm volatile ("cli" ::: "memory");
#elif defined (__aarch64__)
asm volatile ("msr daifset, #15" ::: "memory");
#else
#error Unknown architecture
#endif
// Go through new EFI memmap and free up bootloader entries
size_t entry_count = efi_mmap_size / efi_desc_size;
size_t efi_copy_i = 0;
for (size_t i = 0; i < entry_count; i++) {
EFI_MEMORY_DESCRIPTOR *orig_entry = (void *)efi_mmap + i * efi_desc_size;
EFI_MEMORY_DESCRIPTOR *new_entry = (void *)efi_copy + efi_copy_i * efi_desc_size;
memcpy(new_entry, orig_entry, efi_desc_size);
uint64_t base = orig_entry->PhysicalStart;
uint64_t length = orig_entry->NumberOfPages * 4096;
uint64_t top = base + length;
// Find for a match in the untouched memory map
for (size_t j = 0; j < untouched_memmap_entries; j++) {
if (untouched_memmap[j].type != MEMMAP_USABLE)
continue;
if (top > untouched_memmap[j].base && top <= untouched_memmap[j].base + untouched_memmap[j].length) {
if (untouched_memmap[j].base < base) {
new_entry->NumberOfPages = (base - untouched_memmap[j].base) / 4096;
efi_copy_i++;
if (efi_copy_i == EFI_COPY_MAX_ENTRIES) {
panic(false, "efi: New memory map exhausted");
}
new_entry = (void *)efi_copy + efi_copy_i * efi_desc_size;
memcpy(new_entry, orig_entry, efi_desc_size);
new_entry->NumberOfPages -= (base - untouched_memmap[j].base) / 4096;
new_entry->PhysicalStart = base;
new_entry->VirtualStart = new_entry->PhysicalStart;
length = new_entry->NumberOfPages * 4096;
top = base + length;
}
if (untouched_memmap[j].base > base) {
new_entry->NumberOfPages = (untouched_memmap[j].base - base) / 4096;
efi_copy_i++;
if (efi_copy_i == EFI_COPY_MAX_ENTRIES) {
panic(false, "efi: New memory map exhausted");
}
new_entry = (void *)efi_copy + efi_copy_i * efi_desc_size;
memcpy(new_entry, orig_entry, efi_desc_size);
new_entry->NumberOfPages -= (untouched_memmap[j].base - base) / 4096;
new_entry->PhysicalStart = untouched_memmap[j].base;
new_entry->VirtualStart = new_entry->PhysicalStart;
base = new_entry->PhysicalStart;
length = new_entry->NumberOfPages * 4096;
top = base + length;
}
if (length < untouched_memmap[j].length) {
panic(false, "efi: Memory map corruption");
}
new_entry->Type = EfiConventionalMemory;
if (length == untouched_memmap[j].length) {
// It's a perfect match!
break;
}
new_entry->NumberOfPages = untouched_memmap[j].length / 4096;
efi_copy_i++;
if (efi_copy_i == EFI_COPY_MAX_ENTRIES) {
panic(false, "efi: New memory map exhausted");
}
new_entry = (void *)efi_copy + efi_copy_i * efi_desc_size;
memcpy(new_entry, orig_entry, efi_desc_size);
new_entry->NumberOfPages = (length - untouched_memmap[j].length) / 4096;
new_entry->PhysicalStart = base + untouched_memmap[j].length;
new_entry->VirtualStart = new_entry->PhysicalStart;
break;
}
}
efi_copy_i++;
if (efi_copy_i == EFI_COPY_MAX_ENTRIES) {
panic(false, "efi: New memory map exhausted");
}
}
efi_mmap = efi_copy;
efi_mmap_size = efi_copy_i * efi_desc_size;
efi_boot_services_exited = true;
printv("efi: Exited boot services.\n");
return true;
fail:
panic(false, "efi: Failed to exit boot services");
}
#endif